There can be many possibilities to lose mental health. First, panic attack and the second can be feelings of loneliness and feel being disconnected. These are some of the possibilities that can lead a healthy mind on the onset of craziness and illness. Heart pounding, shaking and dizziness are classic signs of panic disorder. Some people start sweating and trembling for no apparent reason. However, it should not be alarming to you because it is a temporary feeling but if you stuck with the feeling of helplessness for many hours, days and weeks, it surely is an onset of a mental disease. Seek help from a qualified mental health practitioner.